2,3-Epoxypropyl phenyl ethers, a sort of 2,3-epoxypropyl ethers, are important as starting materials for medicaments, particularly, as intermediates for syntheses of .beta.-blockers, since they can be converted into aryloxypropanolamines by ring cleavage using amines, as shown by the following reaction formula: ##STR1##
Also, 2,3-epoxypropyl naphthyl ethers are important, alike the 2,3-epoxypropyl phenyl ethers, as intermediates for syntheses of .beta.-blockers. Further, various valuable compounds were synthesized from 2,3-epoxypropyl benzyl ethers via .gamma.-butyrolactones.
The 2,3-epoxypropyl ethers obtainable by the process of the present invention are important as intermediates for the preparation of medicaments, agricultural chemicals and the like, since they are optically active and so various optically active derivatives can be synthesized starting from them.
Hitherto, as processes for preparing epoxides from the corresponding olefins were known chemical oxidation processes using a peroxide such as hydrogen peroxide or percarboxylic acids as an oxidizing agent, and biochemical oxidation processes using microorganisms. According to the biochemical processes using microorganisms, epoxides were prepared by treating the corresponding linear olefins or the corresponding alkenylbenzenes such as styrene, allylbenzene or the like, with microorganisms belonging to Nocardia, Pseudomonas, Brevibacterium, Corynebacterium, Mycobacterium, Arthrobacter, Acinetobacter, Alcaligenes, Methylo bacterium, Methylococcus, Methylocinus, or the like.
In the epoxidation by means of microorganisms, however, the sorts of olefins which can be epoxidized were limited depending on the sort of the microorganism used. For example, it was reported that Pseudomonas oleovorans did not epoxidize propylene, 1-butene, 2-octene, cis-5-decene, cyclohexene and styrene [S. W. May, R. D. Schwartz, B. J. Abbott and O. S. Zaborsky, Biochim. Biophys. Acta., 403,245-255 (1975)], although .alpha.-olefins of C.sub.6 to C.sub.12 [B. J. Abbott and C. T. Hou, Appl. Microbiol., 26, 86-91 (1973)], .alpha.,.omega.-dienes [S. W. May, R. D. Schwartz, B. J. Abbott and O. S. Zaborsky, Biochim. Biophys. Acta., 403,245-255 (1975)] and allylbenzene [M-J de Smet, J. Kingma, H. Wynberg and B. Witholt, Enzyme Microb. Technol., 5,352-360 (1983)] were epoxidized.
On the other hand, Nocardia corallina epoxidized .alpha.-olefins of C.sub.3 to C18 (Japanese Patent Publication No. 40/81) and also inner olefins such as 2-octene, 3-octene and the like (Japanese Patent Laid-Open No. 141791/83).
Thus, the sorts of olefins which can be epoxidized differ depending on the sort of the microorganism used, and accordingly it is necessary to examine individual olefins and individual microorganisms. As for the oxygen-containing unsaturated compounds such as allyl ethers, among compounds having a C--C double bond, any process for preparing epoxides from them by means of microorganisms is not known as yet.
Moreover, as for the preparation of optically active epoxides by means of microorganisms, any process for preparing optically active epoxides from oxygen-containing unsaturated compounds such as allyl ethers by means of microorganisms is not known as yet, although it is known that optically active epoxides are formed in the preparation of epoxides from linear olefins by microorganisms belonging to Corynebacterium or Pseudomonas and also in the preparation of epoxides from allylbenzene by microorganisms belonging to Pseudomonas.
Now, after making search for microorganisms capable of producing epoxides from allyl ethers, it has been found that epoxide-producing microorganisms belonging to Arthrobacter, Brevibacterium, Corynebacterium, Micrococcus, Nocardia, Pseudomonas or Rhodococcus produce epoxides from the corresponding allyl ethers and that the epoxides produced are optically active. Thus, the present invention has been accomplished.
That is, the object of the present invention resides in providing a novel process for the preparation of 2,3-epoxypropyl ethers valuable as intermediates for preparing medicaments and the like, by means of epoxide-producing microorganisms belonging to Arthrobacter, Brevibacterium, Corynebacterium, Micrococcus, Nocardia, Pseudomonas or Rhodococcus.